title: Reproductive and hormonal factors, family history, and breast cancer according to the hormonal receptor status.
abstract: The aim of this study was to investigate the association between breast cancer risk, reproductive factors, and family history of breast cancer by the estrogen receptor (ER) and progesterone receptor (PR) status. We analyzed data from an Italian case-control study including 1075 women with incident breast cancer and 1477 hospital controls. We estimated the odds ratios (ORs) of breast cancer using unconditional logistic regression models including major recognized risk factors for breast cancer. Stronger associations with ER+ than with ER- breast cancer were observed for parity (OR: 0.7 vs. 0.9 for ≥ 3 births vs. nulliparae), age at first birth (OR: 1.6 vs. 1.2 for age ≥ 30 vs. <25 years), menopausal status (OR: 0.7 vs. 0.8 for postmenopause vs. pre/perimenopause), age at menopause (OR: 1.3 vs. 1.2 for menopause at age ≥ 50 vs. <50 years), and family history of breast cancer (OR: 2.2 vs. 1.4). Among the ER+ patients, the presence of PR+ did not appreciably modify any of the risk estimates. The association with age at menarche and hormone replacement therapy use was neither significant nor heterogeneous across ER and PR subtypes. In conclusion, we found stronger associations with selected menstrual and reproductive factors for ER+ (PR+) than for ER- (PR-) breast cancers, though in the absence of significant heterogeneity.
authors.affiliation: aDepartment of Epidemiology, IRCCS - Istituto di Ricerche Farmacologiche 'Mario Negri' bDepartment of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan cUnit of Epidemiology and Biostatistics, Centro di Riferimento Oncologico, IRCCS, Aviano (PN) dRegistro Tumori della Romagna, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST), Meldola (FO) eUnit of Epidemiology, Istituto Tumori 'Fondazione Pascale', Naples, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Rosato
authors.forename: Cristina
authors.initials: C
authors.lastname: Bosetti
authors.forename: Eva
authors.initials: E
authors.lastname: Negri
authors.forename: Renato
authors.initials: R
authors.lastname: Talamini
authors.forename: Luigino
authors.initials: L
authors.lastname: Dal Maso
authors.forename: Matteo
authors.initials: M
authors.lastname: Malvezzi
authors.forename: Fabio
authors.initials: F
authors.lastname: Falcini
authors.forename: Maurizio
authors.initials: M
authors.lastname: Montella
authors.forename: Carlo
authors.initials: C
authors.lastname: La Vecchia
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D008572:Menarche; D008593:Menopause; D008875:Middle Aged; D016017:Odds Ratio; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D017584:Reproductive History; D012307:Risk Factors; D055815:Young Adult
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human